CONCORD (LN) — U.S. District Judge Paul J. Barbadoro on Tuesday denied Sig Sauer Inc.’s motion for summary judgment in a patent infringement lawsuit brought by NST Global, LLC, finding genuine disputes of material fact over whether the firearm manufacturer’s pivoting contour brace infringes two of NST’s patents for forearm-gripping stabilizing attachments.

NST, which does business as SB Tactical, alleges that Sig Sauer’s pivoting contour brace, or PCB, infringes U.S. Patent No. 8,869,444 and U.S. Patent No. 9,354,021. The patents cover devices designed to help handgun users steady their weapons, particularly when shooting with one hand.

The patents describe a stabilizing attachment with a body that includes a passage for the handgun’s support structure and a lower portion that is “bifurcated so as to define a pair of spaced flaps” to receive a user’s forearm.

Sig Sauer argued its PCB does not literally infringe the patents because the handgun’s support structure is not “telescopically receivable” in the brace’s body. The defense contended that the support structure is attached to the body by a washer, screw, and fastening cap, meaning it cannot be removed without loosening the screw and removing the cap.

Barbadoro rejected that argument, ruling that the “telescopically receivable” limitation is drawn to capability rather than structure. Under Federal Circuit precedent, an accused device infringes if it is “reasonably capable of satisfying the claim limitations” without significant modification.

NST presented evidence that the PCB’s brace flaps can be removed by hand using the thumbscrew included with the product. NST’s expert reported he could “easily remove the brace flap portions [of the accused product] by hand, using components already present on the Accused Products.” The expert performed this removal at a gun shop “by loosening the rear thumb screw by hand with no tools.”

The court found this evidence sufficient to raise a triable issue as to whether the PCB is reasonably capable of removable insertability without significant alteration. Barbadoro noted that Sig Sauer failed to adequately develop its counterarguments regarding insertability, leaving the court unable to assess their merits.

The judge also denied summary judgment on Sig Sauer’s argument that the PCB’s body is not “bifurcated.” Sig Sauer argued the accused product consists of two separate bodies, each with its own flap, rather than a single body that divides into flaps.

Barbadoro pointed to his earlier claim construction order, which determined that the term “body” can be comprised of multiple components. He wrote that a reasonable juror could find that the two separate brace flaps, when assembled and held together at their upper portions, form a single structure that constitutes a single “body.”

The court also addressed Sig Sauer’s procedural argument that NST forfeited its doctrine of equivalents claim by failing to provide a detailed disclosure in its final infringement contentions. While Barbadoro agreed that NST’s disclosure was conclusory and failed to explain “why and how” the doctrine applied, he declined to preclude the claim at this stage.

The judge noted that the local rules allow him to excuse failures to comply when justice requires, and that neither party had sufficiently briefed whether the failure was substantially justified or harmless. He reserved the question of sanctions for a later date.

NST and Sig Sauer were previously in a business relationship, with Sig Sauer serving as the exclusive distributor and licensee of NST’s forearm-stabilizing attachment before developing its own PCB in 2018.

The case is NST Global, LLC v. Sig Sauer Inc., case number 1:19-cv-00792, in the U.S. District Court for the District of New Hampshire.